<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<select>
    <option>请选择</option>
    <option value="0">河北省</option>
    <option value="1">山东省</option>
    <option value="2">北京市</option>

</select>

<select>
    <option>请选择</option>
</select>

<script src="../js/jquery-1.4.2.js"></script>
<script>

    let arr=[["秦始皇岛","唐山","石家庄"],["青岛","菏泽","烟台"],["大兴","朝阳区","东城区"]] ;
    $("select:first").change(function () {
        $("select:last").html("<option>请选择</option>");
        let cities=arr[this.value];
        for (let i = 0; i <cities.length ; i++) {
            let name=cities[i];
            let o=$("<option></option>")
            o.text(name);
            $("select:last").append(o);

        }
    })

</script>
</body>
</html>